1993 Cadillac deville 4.9. I purchased car new in 1993. 230,000 miles. Best car ever... My problem is simple I had to replace a Idle speed control motor about 4 months and used the instruction sheet that came with the parts (after market). I did not have to go through the learn idle speed process. Recently the car is somewhat unstable at idle surges it also is sailing when i let off the gas sometimes rolling along at 35 mph for a minute or two before gas fully retracts. I tried disconnecting the battery with no improvment then I found the sequence for the OBD and have a code E52. I went through the learn idle process last night with temperature at 51 degrees instructions stated be over 50 degrees. The sequence went without any issues and I could hear the idle control motor going through the adjustment process. Car seems to idle perfectly (warm condition) but too low on initial startup (cold condition). Also when I turn engine off I get clicking on the gas pedal about 10 times last 10-15 second or so. My wife thinks it cute and wanted to know if I can get her 2000 seville to do the same tune (not funny). I also get gas pedal clicking when i turn key on before starting but only 2 or 3 clicks on the pedal. Do I need to give this some time to learn the correct idle or do I have some sensor acting up. Also don't know why the cold idle is so low. Any help will be appreicated.

 

This sounds very similar to what my 92 is doing recently. Will be watching this thread and will update if I get mine sorted out.